This is a biobehavioral, longitudinal investigation of the role of emotion in the development of psychopathology in adolescence. The focus is on (a) the role of negative emotions (anger, anxiety, sadness) in the development of psychopathology, and (b) socialization experiences and biological processes that contribute to emotion dysregulation and disorder. The dysregulated experience and expression of emotion is implicated in both externalizing (antisocial patterns) and internalizing (anxiety, depressed mood) disorders. Adolescence is a critical juncture in the development of these disorders. The incidence of psychopathology increases during this time period, and clinical problems become more differentiated along gender lines, i.e. more antisocial behavior in males and more anxiety and depression in females. Adolescents with three levels of (normal, subclinical and clinical) comorbid externalizing and internalizing problems are studied. Youth range in age from 11 to 16 years and are seen at two time points, spaced two years apart. Equal numbers of males and females are studied in order to examine etiology of sex differences in symptoms, emotion regulation, and developmental changes in how disorders manifested. A multi-method, multi-respondent approach is used. Time 1 includes physiological and and neurohormonal functioning (ANS, HPA), behavioral observations of youth and family, experimental paradigms, structured psychatric interviews and questionnaires. Time 2 outcomes are based on interview and questionnaire methods. For a subset of the sample (60 youth)all of the Time 1 procedures were repeated and a new measure (Emotional Stroop Test) added to examine information processing biases for emotional words in clinical groups. Data collection has been completed for both time points and all data files have been constructed. Three recent projects are described below. (1) Time 1 analyses focus on relations between individual differences in symptoms and pubertal development, neuropsychological functioning, affective styles, coping, physiological reactivity and socialization at Time 1. Recent findings indicate that cortisol (an index of HPA function) is differentially related to how males and females experience and cope with stress. Different patterns of relations for emotional and behavioral problems of males and females also were identified for testosterone and DHEA. (2) A project based on Time 2 data and using the Emotional Stroop Test has identified information processing biases in children's internalizing and externalizing problems. Based on both mother and youth reports, youth reports, externalizing problems uniquely predicted longer latencies to anger-related words but not to anxiety-related words. Conversely, internalizing problems tended to show the opposite relations. This work suggests that increased awareness of, and reaction to, personally relevant and challenging stimuli may help to understand the specific nature of adolescents' emotional and behavioral problems. (3) The first analyses to examine prediction of continuity and change in problems over time have emphasized the links between self-esteem, coping style, and anxiety and depression. Males showed higher self esteem than females, while females showed more ruminative coping and anxiety. Youth (both males and females) with high self-esteem showed less ruminative coping and fewer symptoms of anxiety and depression. The nature of the associations between self-esteem and psychiatric symptoms was explained, in part, by the extent to which adolescents also engaged in ruminative coping. Future longitudinal analyses now will examine biological and environmental factors that contribute to increases, decreases, shifts, and lack of change in psychiatric symptoms and psychological problems over time. When these longitudinal analyses are completed they will help to illuminate the interaction of biological factors and socialization experiences that influence the form of expression of psychopathology in adolescent males and females.